ENGCOM-2806: [Backport] Fixed review list ajax if product not exist redirect to 404 page #13102 #17632

 - Merge Pull Request #17632 from mage2pratik/magento2:2.1-develop-PR-port-15369
 - Merged commits:
   1. 81c0320
   2. c729a3b
   3. 53ba0ac
   4. 01a7e20

Author: magento-engcom-team

app/code/Magento/Review/Controller/Product/ListAjax.php

@@ -14,17 +14,16 @@ class ListAjax extends ProductController
     /**
      * Show list of product's reviews
      *
-     * @return \Magento\Framework\View\Result\Layout
+     * @return \Magento\Framework\App\ResponseInterface|\Magento\Framework\Controller\ResultInterface|\Magento\Framework\View\Result\Layout
      */
     public function execute()
     {
         if (!$this->initProduct()) {
-            throw new LocalizedException(__('Cannot initialize product'));
-        } else {
-            /** @var \Magento\Framework\View\Result\Layout $resultLayout */
-            $resultLayout = $this->resultFactory->create(ResultFactory::TYPE_LAYOUT);
+            /** @var \Magento\Framework\Controller\Result\Forward $resultForward */
+            $resultForward = $this->resultFactory->create(ResultFactory::TYPE_FORWARD);
+            return $resultForward->forward('noroute');
         }
 
-        return $resultLayout;
+        return $this->resultFactory->create(ResultFactory::TYPE_LAYOUT);
     }
 }